Semiconductor device structure comprising source and drain protective circuits against electrostatic discharge (ESD)

ABSTRACT

A semiconductor device structure is provided. The semiconductor device structure includes a semiconductor substrate and a gate disposed on the semiconductor substrate. The semiconductor device structure also includes a source doped region and a drain doped region on two opposite sides of the gate. The semiconductor device structure further includes a source protective circuit and a drain protective circuit. From a side perspective view, a first drain conductive element of the source protective circuit partially overlaps a first source conductive element of the drain protective circuit.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. patent application Ser. No.16/661,377 filed on Oct. 23, 2019, the entirety of which is incorporatedby reference herein.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a semiconductor device structure, andin particular to a semiconductor device structure including a staticelectricity protective circuit.

Description of the Related Art

Since the gate oxide structure of a transistor is closer to the drainregion than the source and body regions, resulting in an electronicstatic discharge (ESD), traditional semiconductor devices can easilybecome damaged by the high voltage of an ESD. When ESD current flowsfrom the source region, energy tends to be distributed to a gatedielectric layer rather than to the source/drain doped regions. As aresult, the gate dielectric layer is permanently zapped.

In a traditional semiconductor device, additional elements are oftenused to prevent the transistor from being zapped. However, theseadditional elements occupy space in the whole integrated circuit as wellas making the process harder and causing the cost to go up; therefore,it is necessary to develop a new semiconductor device structure that hasgood protection against ESD.

BRIEF SUMMARY OF THE INVENTION

The disclosure provides a semiconductor device structure. Thesemiconductor device structure includes a semiconductor substrate and agate disposed on the semiconductor substrate. The semiconductor devicestructure also includes a source doped region disposed in thesemiconductor substrate and a drain doped region disposed in thesemiconductor substrate. The source doped region and the drain dopedregion are located on two opposite sides of the gate. The semiconductordevice structure further includes a source protective circuit thatcomprises a plurality of source contact windows disposed on the sourcedoped region and a plurality of first source conductive elementsdisposed on the source contact windows. Every first source conductiveelement is electrically connected to at least one source contact window.In addition, the semiconductor device structure includes a drainprotective circuit that comprises a plurality of drain contact windowsdisposed on the drain doped region and a plurality of first drainconductive elements disposed on the drain contact windows. Every firstdrain conductive element is electrically connected to at least one draincontact window. From a side perspective view, the first drain conductiveelements partially overlap the first source conductive elements.

The disclosure provides a semiconductor device structure. Thesemiconductor device structure includes a semiconductor substrate and agate disposed on the semiconductor substrate and extending in a firstdirection. The semiconductor device structure also includes a sourcedoped region disposed in the semiconductor substrate and extending inthe first direction and a drain doped region disposed in thesemiconductor substrate and extending in the first direction. The sourcedoped region and the drain doped region are located on two oppositesides of the gate. The semiconductor device structure further includes aplurality of source contact windows disposed on the source doped regionand extending in the first direction and a plurality of drain contactwindows disposed on the drain doped region and extending in the firstdirection. In addition, the semiconductor device structure includes afirst source conductive element disposed on the source contact windows.The first source conductive element is electrically connected to thesource doped region and extends in the first direction.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading thesubsequent detailed description and examples with references made to theaccompanying drawings, wherein:

FIG. 1 is a cross-sectional view of a semiconductor device structure inaccordance with some embodiments;

FIG. 2A is a top view of a layout of a semiconductor device structure inaccordance with some embodiments;

FIGS. 2B, 2C, 2D and 2E are side perspective views of the semiconductordevice structure shown in FIG. 2A in accordance with some embodiments;

FIG. 3 is a side perspective view of the semiconductor device structureshown in FIG. 2A in accordance with some embodiments;

FIG. 4A is a top view of a layout of a semiconductor device structure inaccordance with some embodiments;

FIG. 4B is a side perspective view of the semiconductor device structureshown in FIG. 4A in accordance with some embodiments;

FIG. 5A is a top view of a layout of a semiconductor device structure inaccordance with some embodiments;

FIG. 5B is a side perspective view of the semiconductor device structureshown in FIG. 5A in accordance with some embodiments;

DETAILED DESCRIPTION OF THE INVENTION

The semiconductor device structure of the present disclosure isdescribed in detail in the following description. In the followingdetailed description, for purposes of explanation, numerous specificdetails and embodiments are set forth in order to provide a thoroughunderstanding of the present disclosure. The specific elements andconfigurations described in the following detailed description are setforth in order to clearly describe the present disclosure. It will beapparent, however, that the exemplary embodiments set forth herein areused merely for the purpose of illustration, and the inventive conceptmay be embodied in various forms without being limited to thoseexemplary embodiments. In addition, the drawings of differentembodiments may use like and/or corresponding numerals to denote likeand/or corresponding elements in order to clearly describe the presentdisclosure. However, the use of like and/or corresponding numerals inthe drawings of different embodiments does not suggest any correlationbetween different embodiments. In addition, in this specification,expressions such as “first material layer disposed on/over a secondmaterial layer”, may indicate the direct contact of the first materiallayer and the second material layer, or it may indicate a non-contactstate with one or more intermediate layers between the first materiallayer and the second material layer. In the above situation, the firstmaterial layer may not be in direct contact with the second materiallayer.

It should be noted that the elements or devices in the drawings of thepresent disclosure may be present in any form or configuration known tothose skilled in the art. In addition, the expression “a layer overlyinganother layer”, “a layer is disposed above another layer”, “a layer isdisposed on another layer” and “a layer is disposed over another layer”may indicate that the layer is in direct contact with the other layer,or that the layer is not in direct contact with the other layer, therebeing one or more intermediate layers disposed between the layer and theother layer.

In addition, in this specification, relative expressions are used. Forexample, “lower”, “bottom”, “higher” or “top” are used to describe theposition of one element relative to another. It should be appreciatedthat if a device is flipped upside down, an element that is “lower” willbecome an element that is “higher”.

The terms “about” and “substantially” typically mean +/−20% of thestated value, more typically +/−10% of the stated value, more typically+/−5% of the stated value, more typically +/−3% of the stated value,more typically +/−2% of the stated value, more typically +/−1% of thestated value and even more typically +/−0.5% of the stated value. Thestated value of the present disclosure is an approximate value. Whenthere is no specific description, the stated value includes the meaningof “about” or “substantially”.

It should be understood that, although the terms first, second, thirdetc. may be used herein to describe various elements, components,regions, layers, portions and/or sections, these elements, components,regions, layers, portions and/or sections should not be limited by theseterms. These terms are only used to distinguish one element, component,region, layer, portion or section from another region, layer or section.Thus, a first element, component, region, layer, portion or sectiondiscussed below could be termed a second element, component, region,layer, portion or section without departing from the teachings of thepresent disclosure.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this disclosure belongs. It should be appreciated that,in each case, the term, which is defined in a commonly used dictionary,should be interpreted as having a meaning that conforms to the relativeskills of the present disclosure and the background or the context ofthe present disclosure, and should not be interpreted in an idealized oroverly formal manner unless so defined.

This description of the exemplary embodiments is intended to be read inconnection with the accompanying drawings, which are to be consideredpart of the entire written description. The drawings are not drawn toscale. In addition, structures and devices are shown schematically inorder to simplify the drawing.

In the description, relative terms such as “lower,” “upper,”“horizontal,” “vertical,”, “above,” “below,” “up,” “down,” “top” and“bottom” as well as derivative thereof (e.g., “horizontally,”“downwardly,” “upwardly,” etc.) should be construed to refer to theorientation as then described or as shown in the drawing underdiscussion. These relative terms are for convenience of description anddo not require that the apparatus be constructed or operated in aparticular orientation. Terms concerning attachments, coupling and thelike, such as “connected” and “interconnected,” refer to a relationshipwherein structures are secured or attached to one another eitherdirectly or indirectly through intervening structures, as well as bothmovable or rigid attachments or relationships, unless expresslydescribed otherwise.

It should be noted that the present disclosure presents embodiments of asemiconductor device structure, and may be included in an integratedcircuit (IC) such as a microprocessor, memory device, and/or another IC.The IC may also include various passive and active microelectronicdevices, such as thin film resistors, other capacitors (e.g.metal-insulator-metal capacitor, MIMCAP), inductors, diodes,metal-oxide-semiconductor field effect transistors (MOSFETs),complementary MOS (CMOS) transistors, bipolar junction transistors(BJTs), laterally diffused MOS (LDMOS) transistors, high power MOStransistors, or other types of transistors. One of ordinary skill mayrecognize other embodiments of semiconductor devices that may benefitfrom aspects of the present disclosure.

Refer to FIG. 1 , which illustrates a cross-sectional view of asemiconductor device structure 100 in accordance with some embodiments.As shown in FIG. 1 , the semiconductor device structure 100 includes asemiconductor substrate 110. The semiconductor substrate 110 may be abulk semiconductor, a semiconductor-on-insulator (SOI) substrate, or thelike, which may be doped (e.g., with a p-type or an n-type dopant) orundoped. The semiconductor substrate 110 may be a wafer, such as asilicon wafer. Generally, an SOI substrate is a layer of a semiconductormaterial formed on an insulator layer. The insulator layer may be, forexample, a buried oxide (BOX) layer, a silicon oxide layer, or the like.The insulator layer is provided on a substrate, typically a silicon or aglass substrate. Other substrates, such as a multi-layered or gradientsubstrate may also be used. In some embodiments, the semiconductormaterial of the semiconductor substrate 110 may include silicon;germanium; a compound semiconductor including silicon carbide, galliumarsenic, gallium phosphide, indium phosphide, indium arsenide, and/orindium antimonide; an alloy semiconductor including SiGe, GaAsP, AlInAs,AlGaAs, GalnAs, GaInP, and/or GaInAsP; or combinations thereof. In someembodiments, the semiconductor substrate 110 has a first conductivetype, such as P type.

In addition, the semiconductor device structure 100 may include anepitaxial layer (not shown) disposed on the semiconductor substrate 110.The epitaxial layer may include, but is not limited to, Si, Ge, SiGe,III-V compound, or a combination thereof. The epitaxial layer may beformed by an epitaxial growth step, such as metal-organic chemical vapordeposition (MOCVD), metal-organic vapor phase epitaxy (MOVPE),plasma-enhanced chemical vapor deposition (PECVD), remoteplasma-enhanced chemical vapor deposition (RP-CVD), molecular beamepitaxy (MBE), hydride vapor phase epitaxy (HYPE), liquid phase epitaxy(LPE), chloride vapor phase epitaxy (Cl-VPE), or any other suitablemethod. In some embodiments, the epitaxial layer has the firstconductive type, such as P type.

As shown in FIG. 1 , the semiconductor device structure 100 includes awell region 120 formed within the semiconductor substrate 110.Alternatively, the well region 120 can be formed within the epitaxiallayer mentioned above. In some embodiments, the well region 120 has thefirst conductive type, such as P type. The dopant concentration of thewell region 120 is between about 10¹² atoms/cm³ to about 10¹⁷ atoms/cm³.

As shown in FIG. 1 , the semiconductor device structure 100 includes aplurality of isolation regions 130. In some embodiments, the isolationregion 130 is a shallow trench isolation (STI). The semiconductorsubstrate 110 can be patterned by a photolithography and an etchingprocess to form multiple openings, and then dielectric material can fillinto the openings by a deposition process, thereby forming the STI. Insome embodiments, the isolation region 130 is a field oxide regionsformed by oxidation of silicon. The photolithography process includesphotoresist coating (e.g., spin-on coating), soft baking, maskalignment, exposure, post-exposure baking, developing the photoresist,rinsing and drying (e.g., hard baking). The photolithography process mayalso be implemented or replaced by another proper method such asmaskless photolithography, electron-beam writing or ion-beam writing.The etching process may include dry etching, wet etching, and otheretching methods such as reactive ion etching (RIE). Furthermore, theetching process may also include purely chemical etching (plasmaetching), purely physical etching (ion milling), or a combinationthereof. The deposition process may include chemical vapor deposition(CVD), physical vapor deposition (PVD), atomic layer deposition (ALD)and other deposition process.

As shown in FIG. 1 , the semiconductor device structure 100 includes asource doped region 140, a drain doped region 150 and a gate 160. Thesource doped region 140 and the drain doped region 150 are located ontwo opposite sides of the gate 160. In some embodiments, the sourcedoped region 140 and the drain doped region 150 have a second conductivetype, such as N type, different than the first conductive type. Thedopant concentration of the source doped region 140 and/or the draindoped region 150 is between about 10¹⁹ atoms/cm³ to about 10²¹atoms/cm³. The source doped region 140 and the drain doped region 150may be formed by an ion implantation process or a diffusion processfollowed by a rapid thermal annealing (RTA) to activate the implanteddopants.

As shown in FIG. 1 , the gate 160 includes a gate dielectric layer 162and a gate electrode 164. The material of the gate dielectric layer 162may include, but is not limited to, silicon oxide, silicon nitride,silicon oxynitride, high-k material, any other suitable dielectricmaterial, or a combination thereof. The high-k material may include, butis not limited to, metal oxide, metal nitride, metal silicide,transition metal oxide, transition metal nitride, transition metalsilicide, transition metal oxynitride, metal aluminate, zirconiumsilicate, zirconium aluminate. For example, the material of the high-kmaterial may include, but is not limited to, LaO, AlO, ZrO, TiO, Ta₂O₅,Y₂O₃, SrTiO₃(STO), BaTiO₃(BTO), BaZrO, HfO₂, HfO₃, HfZrO, HfLaO, HfSiO,HfSiON, LaSiO, AlSiO, HfTaO, HfTiO, HfTaTiO, HfAlON, (Ba,Sr)TiO₃(BST),Al₂O₃, any other suitable high-k dielectric material, or a combinationthereof. The gate dielectric layer 162 may be formed by CVD or spin-oncoating. The CVD may include, but is not limited to, low pressurechemical vapor deposition (LPCVD), low temperature chemical vapordeposition (LTCVD), rapid thermal chemical vapor deposition (RTCVD),PECVD, or any other suitable method.

The material of the gate electrode 164 may include, but is not limitedto, amorphous silicon, poly-silicon, one or more metal, metal nitride,conductive metal oxide, or a combination thereof. The metal may include,but is not limited to, molybdenum, tungsten, titanium, tantalum,platinum, or hafnium. The metal nitride may include, but is not limitedto, molybdenum nitride, tungsten nitride, titanium nitride or tantalumnitride. The conductive metal oxide may include, but is not limited to,ruthenium oxide or indium tin oxide. The conductive material layer maybe formed by CVD, sputtering, resistive thermal evaporation, electronbeam evaporation, or any other suitable method.

In some embodiments, the semiconductor device structure 100 includes abody region 170. The body region 170 has the first conductive type. Thedopant concentration of the body region 170 is between about 10¹⁹atoms/cm³ to about 10²¹ atoms/cm³. As shown in FIG. 1 , the source dopedregion 140 is separated from the body region 170 by the isolation region130. In addition, the drain doped region 150, the source doped region140, the gate 160 and the body region 170 can be connected to outervoltage D, S, G and B, respectively; however, the scope of thedisclosure is not intended to be limited.

Refer to FIG. 2A, which illustrates a top view of a layout of asemiconductor device structure 200A in accordance with some embodiments.It should be noted that in order to illustrate clearly the layout ofconductive elements, doped regions and conductive holes of thesource/drain region, some elements are omitted in FIG. 2 .

As shown in FIG. 2A, the semiconductor device structure 200A includes agate 210, a source doped region 220 and a drain doped region 230 thatcan correspond to the gate 160, the source doped region 140 and thedrain doped region 150 respectively, and are not repeated herein. Thegate 210, the source doped region 220 and the drain doped region 230extend along the first direction, such as Y direction. Morespecifically, the longer side of the gate 210, the source doped region220 and/or the drain doped region 230 is substantially parallel to thefirst direction. In addition, the semiconductor device structure 200Amay include multiple gates 210, source doped regions 220 and/or draindoped regions 230 that are arranged along the second direction, such asthe X direction. The semiconductor device structure 200A may alsoinclude a body region (not shown), which encloses the previouslydescribed multiple gates 210, source doped regions 220 and drain dopedregions 230. Moreover, some isolation regions (not shown) are formed toelectrically isolate different active elements.

Next, as shown in FIG. 2A, the semiconductor device structure 200Aincludes a source protective circuit 250 a and a drain protectivecircuit 260 a. Refer to FIG. 2B, which illustrates a side perspectiveview along C-C line of the semiconductor device structure 200A shown inFIG. 2A. The semiconductor device structure 200A includes asemiconductor substrate 240 that is the same as or similar to thesemiconductor substrate 110, and is not repeated herein. As shown inFIG. 2B, the semiconductor device structure 200A includes interlayerdielectric (ILD) 242, 244, 246 and 248 on the semiconductor substrate240. In some embodiments, the ILD 242, 244, 246 and 248 are flowablefilms formed by FCVD. In some embodiments, the ILD 242, 244, 246 and 248are formed by dielectric materials, such as phospho-silicate glass(PSG), boro-silicate glass (BSG), boron-doped phospho-silicate glass(BPSG), undoped silicate glass (USG), or the similar materials; the ILD242, 244, 246 and 248 may be deposited by suitable process, such as CVD,spin coating, PECVD or a combination thereof.

In some embodiments, as shown in FIGS. 2A and 2B, the source protectivecircuit 250 a includes a plurality of source contact windows 222, sourceconductive holes 224 and first source conductive elements 226. Inaddition, the semiconductor device structure 200 may include a silicidelayer (not shown), which is formed between the source doped region 220and the source contact window 222. In some embodiments, a metal materialmay be deposited on the semiconductor substrate 240 followed byperforming an annealing process. Next, the metal material reacts withthe surface of the semiconductor substrate 240 so that the silicidelayer can be formed on the surface of the semiconductor substrate 240.After the silicide layer is formed, remaining metal material notreacting with the semiconductor substrate 240 is removed. The remainingmetal material can be removed by an etching process, such as wet etchingprocess, dry etching process, another suitable etching process, or acombination thereof.

In some embodiments, the source contact windows 222 are disposed on thesemiconductor substrate 240. The source contact windows 222 areelectrically connected to the source doped region 220. The sourcecontact window 222 may include a barrier layer and a conductive layer.The barrier layer may include titanium, titanium nitride, tantalum,tantalum nitride or the like. The material of the conductive layer mayinclude copper, copper alloy, silver, gold, tungsten, aluminum, nickel,cobalt or the like.

As shown in FIG. 2B, the first source conductive element 226 aredisposed on the source contact window 222 and in contact with the sourcecontact window 222. The first source conductive elements 226 areelectrically connected to the source doped region 220. The first sourceconductive element 226 may include metal material, such as copper,titanium, cobalt, tungsten, nickel. In addition, the first sourceconductive element 226 may also include a barrier layer. The firstsource conductive element 226 may be formed by PVD, CVD, spin coating,other suitable process or a combination thereof. In some embodiments, asshown in FIGS. 2A and 2B, the first source conductive element 226extends in the first direction, such as Y-direction. More specifically,the longer side of the first source conductive element 226 issubstantially parallel to the first direction. In some embodiments, onefirst source conductive element 226 is in physical contact with at leasttwo source contact windows 222.

As shown in FIG. 2B, the source conductive holes 224 are disposed on thefirst source conductive element 226, and in physical contact with thesource doped region 220. The source conductive hole 224 may be made of amaterial that is the same or similar to that of the source contactwindow 222, and it is not repeated herein. As shown in FIG. 2A, thesource conductive hole 224 does not overlap the source contact window222 from a top view. More specifically, the region where the sourceconductive hole 224 projects onto the semiconductor substrate 240 doesnot overlap the region where the source contact window 222 projects ontothe semiconductor substrate 240. In this embodiment, one first sourceconductive element 226 is in physical contact with two source contactwindows 222 and one source conductive hole 224.

As shown in FIGS. 2A and 2B, the source protective circuit 250 a furtherincludes a second source conductive element 228 disposed on the sourceconductive hole 224. The second source conductive element 228 may bemade of a material that is the same or similar to that of the firstsource conductive element 226, and it is not repeated herein. In someembodiments, the second source conductive element 228 extends in thefirst direction. More specifically, the longer direction of the secondsource conductive element 228 is substantially parallel to the firstdirection. In some embodiments, one second source conductive element 228covers multiple first source conductive elements 226.

Refer to FIG. 2C, which illustrates a cross-sectional view of thesemiconductor device structure 200A along D-D line. In some embodiments,as shown in FIGS. 2A and 2C, the semiconductor device structure 200Aincludes a plurality of drain contact windows 232, drain conductiveholes 234 and first drain conductive elements 236. Further, thesemiconductor device structure 200A includes a silicide layer (notshown) formed between the drain doped region 230 and the drain contactwindow 232.

In some embodiments, the drain contact windows 232 are disposed on thesemiconductor substrate 240. The drain contact windows 232 areelectrically connected to the drain doped region 230. The drain contactwindow 232 may include a barrier layer and a conductive layer. Thebarrier layer may include titanium, titanium nitride, tantalum, tantalumnitride or the like. The material of the conductive layer may includecopper, copper alloy, silver, gold, tungsten, aluminum, nickel, cobaltor the like.

As shown in FIG. 2C, the first drain conductive element 236 are disposedon the drain contact window 232 and in contact with the drain contactwindow 232. The first drain conductive elements 236 are electricallyconnected to the drain doped region 230. The first drain conductiveelement 236 may include metal material, such as copper, titanium,cobalt, tungsten, nickel. In addition, the first drain conductiveelement 236 may also include a barrier layer. The first drain conductiveelement 236 may be formed by PVD, CVD, spin coating, other suitableprocess or a combination thereof. In some embodiments, as shown in FIGS.2A and 2C, the first drain conductive element 236 extends in the firstdirection. More specifically, the longer side of the first drainconductive element 236 is substantially parallel to the first direction.In some embodiments, one first drain conductive element 236 is inphysical contact with at least two drain contact windows 232.

As shown in FIG. 2C, the drain conductive holes 234 are disposed on thefirst drain conductive elements 236, and in physical contact with thedrain doped region 230. The drain conductive hole 234 may be made of amaterial that is the same or similar to that of the drain contact window232, and it is not repeated herein. As shown in FIG. 2A, the drainconductive hole 234 does not overlap the drain contact window 232 fromthe top view. More specifically, the region where the drain conductivehole 234 projects onto the semiconductor substrate 240 does not overlapthe region where the drain contact window 232 projects onto thesemiconductor substrate 240. In this embodiment, one first drainconductive element 236 is in physical contact with two drain contactwindows 232 and one drain conductive hole 234.

As shown in FIGS. 2A and 2C, the second drain conductive element 238 isdisposed on the drain conductive hole 234. The second drain conductiveelement 238 may be made of a material that is the same or similar tothat of the first drain conductive element 236, and it is not repeatedherein. In some embodiments, the second drain conductive element 238extends in the first direction. More specifically, the longer directionof the second drain conductive element 238 is substantially parallel tothe first direction. In some embodiments, one second drain conductiveelement 238 covers multiple first drain conductive elements 236.

In some embodiments, the first source conductive element 226 of thesource protective circuit 250 a does not extend to the region directlyover the drain doped region 230. Namely, the region where the firstsource conductive element 226 projects onto the surface of thesemiconductor substrate 240 does not overlap the drain doped region 230.The first drain conductive element 236 of the drain protective circuit260 a does not extend to the region directly over the source dopedregion 220. Namely, the region where the first drain conductive element236 projects onto the surface of the semiconductor substrate 240 doesnot overlap the source doped region 220. The layout mentioned above mayassist in simplifying the process and improving the yield of thesemiconductor device structure 200A.

In some embodiments, as shown in FIG. 2A, the source contact windows 222of the source protective circuit 250 a are not aligned with the draincontact windows 232 of the drain protective circuit 260 a. Morespecifically, the arrangement of the source contact windows 222 offsetsthe arrangement of the drain contact windows 232. An imaginary lineextending in the second direction would not pass through the sourcecontact window 222 and the drain contact window 232 simultaneously.

In some embodiments, the source conductive holes 224 of the sourceprotective circuit 250 a are not aligned with the drain conductive holes234 of the drain protective circuit 260 a. More specifically, thearrangement of the source conductive holes 224 offsets the arrangementof the drain conductive holes 234. An imaginary line along the seconddirection would not pass through the source conductive hole 224 and thedrain conductive hole 234 simultaneously.

In some embodiments, the first source conductive element 226 of thesource protective circuit 250 a is not aligned with the first drainconductive element 236 of the drain protective circuit 260 a. Forexample, there is a distance between the shorter side of the firstsource conductive element 226 and the shorter side of the first drainconductive element 236 along the first direction. More specifically, theshorter side of the first source conductive element 226 is not alignedwith the shorter side of the first drain conductive element 236. In someembodiments, the second source conductive element 228 of the sourceprotective circuit 250 a is aligned with the second drain conductiveelement 238 of the drain protective circuit 260 a. For example, theshorter side of the second source conductive element 228 is aligned withthe shorter side of the second drain conductive element 238. Inaddition, the first source conductive element 226 is separated from thefirst drain conductive element 236; the first source conductive element226 is not electrically connected to the first drain conductive element236. The second source conductive element 228 is separated from thesecond drain conductive element 238; the second source conductiveelement 228 is not electrically connected to the second drain conductiveelement 238.

Refer to FIG. 2D, which illustrates a cross-sectional view of thesemiconductor device structure 200A along A-A line. In some embodiments,as shown in FIG. 2D, the source doped region 220 and the drain dopedregion 230 are located on two sides of the gate 210. The gate 210includes a gate dielectric layer 212 and a gate electrode 214 that maybe the same as or similar to the gate dielectric layer 162 and the gateelectrode 164 respectively, and are not repeated herein. In someembodiments, in a cross-sectional plane having the source contact window222, there is no drain contact window 232 formed over the drain dopedregion 230. In some embodiments, in a cross-sectional plane having thedrain conductive hole 234, there is no source conductive hole 224 formedover the first source conductive element 226. In some embodiments, thesource contact window 222 and the drain conductive hole 234 are locatedin the same cross-sectional plane.

Moreover, as shown in FIG. 2D, the first source conductive element 226and the first drain conductive element 236 are located in the samehorizontal layer. More specifically, the first source conductive element226 and the first drain conductive element 236 are disposed on the ILD242. The second source conductive element 228 and the second drainconductive element 238 are located in the same horizontal layer. Morespecifically, the second source conductive element 228 and the seconddrain conductive element 238 are disposed on the ILD 246.

Refer to FIG. 2E, which illustrates a cross-sectional view of thesemiconductor device structure 200A along B-B line. In some embodiments,in a cross-sectional plane having the drain contact window 232, there isno source contact window 222 formed over the source doped region 220. Insome embodiments, in a cross-sectional plane having the sourceconductive hole 224, there is no drain conductive hole 234 formed overthe first drain conductive element 236. In some embodiments, the draincontact window 232 and the source conductive hole 224 are located in thesame cross-sectional plane.

Refer to FIG. 3 , which illustrates the side perspective view of thesemiconductor device structure 200A shown in FIG. 2A in accordance withsome embodiments of the disclosure. More specifically, FIG. 3 is thefigure that the cross-sectional view of FIG. 2B overlapped that of FIG.2C. It should be noted that the elements of FIG. 2B are illustrated as asolid line, and the elements of FIG. 2C are illustrated as a dashedline. As shown in FIG. 3 , the source contact window 222 does notoverlap the drain contact window 232; the source conductive hole 224does not overlap the drain conductive hole 234. In some embodiments, thefirst source conductive element 226 overlaps a portion of the firstdrain conductive element 236. In some embodiments, the first sourceconductive element 226 does not completely overlap the first drainconductive element 236; the source conductive hole 224 and/or the drainconductive hole 234 is disposed within these overlapping regions.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some embodiments, the layout of the protective circuitshas other patterns. Refer to FIGS. 4A and 4B, which illustrate a topview of the layout and a cross-sectional view of the semiconductordevice structure 200B along E-E line, respectively. As shown in FIG. 4A,the semiconductor device structure 200B includes a source protectivecircuit 250 b and a drain protective circuit 260 b. The sourceprotective circuit 250 b includes the source contact window 222, sourceconductive hole 224, first source conductive element 226 and secondsource conductive element 228; the drain protective circuit 260 bincludes the drain contact window 232, drain conductive hole 234, firstdrain conductive element 236 and second drain conductive element 238. Insome embodiments, one first source conductive element 226 of the sourceprotective circuit 250 b is in contact with one source contact window222 and two source conductive holes 224. In some embodiments, one firstdrain conductive element 236 of the drain protective circuit 260 b is incontact with one drain contact window 232 and two drain conductive holes234.

Many variations and/or modifications can be made to embodiments of thedisclosure. Refer to FIGS. 5A and 5B, which illustrate a top view of thelayout and a cross-sectional view of the semiconductor device structure200C along F-F line, respectively. As shown in FIG. 5A, thesemiconductor device structure 200C includes a source protective circuit250 c and a drain protective circuit 260 c. The source protectivecircuit 250 c includes the source contact window 222, source conductivehole 224, first source conductive element 226 and second sourceconductive element 228; the drain protective circuit 260 c includes thedrain contact window 232, drain conductive hole 234, first drainconductive element 236 and second drain conductive element 238. In someembodiments, one first source conductive element 226 of the sourceprotective circuit 250 c is in contact with three source contact window222 and two source conductive holes 224. In some embodiments, one firstdrain conductive element 236 of the drain protective circuit 260 c is incontact with three drain contact window 232 and two drain conductiveholes 234. In some embodiments, the number of source contact windows 222in physical contact with the first source conductive element 226 isdifferent than the number of source conductive holes 224 in physicalcontact with the first source conductive element 226. In someembodiments, the number of drain contact windows 232 in physical contactwith the first drain conductive element 236 is different than the numberof drain conductive holes 234 in physical contact with the first drainconductive element 236.

It should be noted that the number of source conductive elements inphysical contact with the source contact window or the source conductivehole, or the number of drain conductive elements in physical contactwith the drain contact window or the drain conductive hole, shown inabove figures, is merely exemplary. In other embodiments, the number canbe modified. In addition, the first source conductive element 226 andthe first drain conductive element 236 can also be referred to as thefirst metal layer; the second source conductive element 228 and thesecond drain conductive element 238 can also be referred to as thesecond metal layer.

Although some embodiments of the present disclosure and their advantageshave been described in detail, it should be understood that variouschanges, substitutions and alterations can be made herein withoutdeparting from the spirit and scope of the disclosure as defined by theappended claims. For example, it will be readily understood by thoseskilled in the art that many of the features, functions, processes, andmaterials described herein may be varied while remaining within thescope of the present disclosure. Moreover, the scope of the presentapplication is not intended to be limited to the particular embodimentsof the process, machine, manufacture, composition of matter, means,methods and steps described in the specification. As one of ordinaryskill in the art will readily appreciate from the disclosure of thepresent disclosure, processes, machines, manufacture, compositions ofmatter, means, methods, or steps, presently existing or later to bedeveloped, that perform substantially the same function or achievesubstantially the same result as the corresponding embodiments describedherein may be utilized according to the present disclosure. Accordingly,the appended claims are intended to include within their scope suchprocesses, machines, manufacture, compositions of matter, means,methods, or steps.

What is claimed is:
 1. A semiconductor device structure, comprising: asemiconductor substrate; a gate disposed on the semiconductor substrate;a source doped region disposed in the semiconductor substrate; a draindoped region disposed in the semiconductor substrate, wherein the sourcedoped region and the drain doped region are located on two oppositesides of the gate; a source protective circuit, comprising: a pluralityof source contact windows disposed on the source doped region; and aplurality of first source conductive elements disposed on the sourcecontact windows, wherein every first source conductive element iselectrically connected to at least one source contact window; a secondsource conductive element covering the first source conductive elements;and a drain protective circuit, comprising: a plurality of drain contactwindows disposed on the drain doped region; and a plurality of firstdrain conductive elements disposed on the drain contact windows, whereinevery first drain conductive element is electrically connected to atleast one drain contact window; wherein from a side perspective view,the first drain conductive elements partially overlap the first sourceconductive elements.
 2. The semiconductor device structure as claimed inclaim 1, wherein the first source conductive elements are separated fromthe first drain conductive elements.
 3. The semiconductor devicestructure as claimed in claim 1, wherein at least one first sourceconductive element is in physical contact with two source contactwindows.
 4. The semiconductor device structure as claimed in claim 1,wherein the source protective circuit further comprises a plurality ofsource conductive holes disposed on the first source conductive elementsand electrically connected to the source doped region, wherein from atop view, the source conductive holes do not overlap the source contactwindows.
 5. The semiconductor device structure as claimed in claim 4,wherein at least one first source conductive element is in physicalcontact with two source conductive holes.
 6. The semiconductor devicestructure as claimed in claim 4, wherein the number of source contactwindows in contact with one first source conductive element is differentthan the number of source conductive holes in contact with one firstsource conductive element.
 7. The semiconductor device structure asclaimed in claim 1, wherein the source protective circuit does notextend above the drain doped region.
 8. The semiconductor devicestructure as claimed in claim 1, wherein the first source conductiveelement does not extend above the drain doped region.
 9. Thesemiconductor device structure as claimed in claim 1, wherein from theside perspective view, the source contact windows do not overlap thedrain contact windows.